Charter's latest debt packaging would support an offer with a cash component of almost $90 a share, according to the sources. The rest of the payment would likely be in Charter stock. The company has been making a bid for Time Warner Cable for months but efforts have thus far been rejected.

Charter could be facing competition, however, against media giants such as Cox Communications and Comcast, both of which are considering whether to make bids. (Comcast is the parent company of NBCUniversal.)

Sources told Dow Jones that Time Warner Cable would be more receptive to a sale to Cox or Comcast as a deal with Charter could be financially risky.